第5章

TOascertainthecorrectformulaofasubstantiallypermanentink，aswehavelearned，hasbeentheaimduringacenturyormore，ofablechemists，manufacturersandlaymen。Theirexperimentsandstudyofancientandmoderndocumentsallpointunerringlyinthedirectionofaninkcontainingironandgalls。

Accumulatedevidencemaybesaidtoestablishitselfinthelightofinvestigationandexperienceandbecomesmoreandmoreacertaintywhenconsidered，reviewedanddiscussedinconnectionwithachronologicalhistoryofthe“gall“inkssincetheycameintosemi-officialandotherusescenturiesago。

DescriptionsofMSS。containinginkwritingshundredsofyearsold，manyofthemaslegibleaswhenfirstwritten，aresilentwitnesseswhosetestimonycannotbeassailed。Suchinformationwhenassembledtogetherminimizesmanyoftheconditionswhichhaveexistedandinterposedinpreventingduringthelastfourdecadesageneraladoptionorre-adoptionofsuchatanno-gallateofironink，thelastingqualitiesofwhichsomeofourforefathersestimatedwould，andasweknowhavestoodthetestoftime。

Assumingthischaracterofinktohavebeenemployedinpastcenturies，thecauseorcausesforthedifferentiationsinrespecttocoloranddurabilitybecomeofparamountimportance。

Theinvestigationsofthewriterinthisdirection，whileinsomerespectstravelingthesameroadfollowedbyothers，divergedfromthemandhasbeenmoreinthenatureofacomparativeanalyticalandmicroscopicexaminationofancientwithancientandmodernwithmoderndocumentsinconnectionwithnumerouschemicalexperiments，themanufactureofhundredsofinksandthestudyoftheirtimeandotherphenomena。

Toaccomplishthis，ancientdocumentsnotwrittenwith“Indian“ink，butwiththoseobviouslycontainingcombinationsofironandgallsorothertannins，wereselectedandgroupedintocolorfamilies。

Theybeganwiththefourteenthcentury，continuingwellintothenineteenth，tothenumberofnearlyfourhundred，eachofthemofadifferentdateanddifferentyear。Someofthemweresopaleandindistinctastobeillegible，otherslesssoandbygradualstepstheyapproachedtoadefiniteblack；manyofthemasrichanddeepincolorasiftheyhadbeenwrittennotcenturiesagobutwithinafewyears。Signaturesonthesamedocumentrepresenteddifferentdegreesofcolor，sothatthequestionofthematerialonwhichthewritingappearedaffectingtheappearanceoftheink，wasnotafactor；butthedifferenceintheinksusedtomakethesignatureswasthedeterminingfactor。

AtthispointitmaybenotedthattheinvestigationsconductedbyMr。Swanbeforereferredtoandthosebythewriterandtheresultantobservationsofeachweresubstantiallyalike。Manyofthewriter’s，however，precededthoseofMr。Swan’s，forduringtheyears1885and1886，havinghadthecustodyofpartoftheArchivesoftheCityofNewYorkthereweremanyopportunitiestostudythissubjectwhichweretakenadvantageof，beforeandafterwhichtimefrequentexaminationsweremadeofwritingsmuchmoreancientthanthosepertainingtoNewYork。

Assumingasecondpremisewastoassertthattheinksemployedinthewritingofthesedocumentswere“straight“orpossessedsome“added“pigmentorcolor。Again，thevehiclestoholdtheparticlesorpossiblypreservingsubstances，mightbefactors。

Allliteraturepossiblereferringtoinkformulaswasexaminedtoascertainthenamesofmaterialsrecommendedorformerly“added“togallinks，becauseifthepristinenessoftheblackerinkswasduetotheaddedpigmentitwasasafepropositionthatitwasstillexistentintheink，andthatifitcouldbediscoveredpartatleastoftheproblemwouldbe，simplified。

The“added“colorcompounds，excludingthoseoftheanilinefamilywhichpertaintothemoremoderninkcompositions，areoftwoclasses：thosepossessingtanninandcolor-yieldingmaterialsandthosecontainingonlyacolor-yieldingmaterial。Manyofthefirstclasshavebeenusedinthemanufactureofinkbothwithinfusionsofnut-gallsoralone，whilebutveryfewofthesecondclasshavebeenusedforeitherpurpose。

Thedecomposingactionoflight，oxygenandmoistureonmanyofeachclassplacedthembeyondthepurviewofconsideration，whilethedatesofthediscoveryandthefactofthesmallpercentageoftannincontainedinotherspermittedthemalsotobediscarded。Forinstance：vanadium，whichisfairlypermanent，wasdiscoveredonlyin1830；chanchi，theinkplantofNewGranadadiscoveredinthesixteenthcentury，possessingexcellentlastingqualities，doesnotassimilateperfectlywithotherconstituentsusedinthemanufactureofink，butisbestwhenusedalone；

Berlinblue(prussianblue)iswellspokenof，butwasonlydiscoveredbyaccidentin1710byDiesbach，apreparerofcolorsatBerlin；logwood，moreusedforthispurposethananyothermaterial，wasfirstimportedintoEuropeinthesixteenthcenturyandcausesadeteriorationofthedurablequalitiesofthetanno-gallateofiron；Brazil-woodandarchil，andtheirallies，areexceedinglyfugitive；bablah，thefruitoftheacaciaarabica，myrabolams，ofChinesegrowth，catechu，andsumacwhichthoughusedinthetimeofPliny，eachcontainsapercentageofgallicacidtoosmalltomeettherequirements。

Divi-divi，aSouthAmericanproduct，cameintouseonlyattheendofthesixteenthcenturyandhasnotstoodthetestoftime。

Thissiftingprocesscompletelyeliminatedallbutlampblack，madderandindigoinsomeformasapermanent“added“colorpigment。Lampblack，whichisweknowformsthebasisof“Indian“ink，isnotsolubleandrequiresaveryheavygummyvehicletopreventitsimmediateprecipitation，andwhileitcouldhavebeenusedincombinationwithtanno-gallateofironasanink，thefactthatitwaspossibletochemicallyremovetheancientinkswhichremainedblack，wasasufficientdemonstrationthatthiscarbonsubstance，whichisnotaffectedbychemicals，eitherascontainedinthefluidinkorasdustedonafterwriting，couldhaveformednopartoftheancienttanno-gallateofironinks。

MadderismentionedasofveryancienttimesandwascultivatedinEuropeasearlyasthetenthcentury；

itsadditiontoanironandgallinkissaidtobeaninventionoftheyear1855；itiscertain，however，thatitwasusedforalikepurposeasearlyas1826，andafairpresumptionthatitwasfrequentlyemployedinsomeformduringtheprecedingfourcenturies。Ithasundercertainconditionsverylastingpropertiesasthemadder-dyedclothsfoundwrappedaroundEgyptianmummiesdemonstrates，butdoesnotassistthetanno-gallateofirontoretainitsblackcolor；onthecontraryitseemstolessenthisquality。

Thatindigoforaddedcolorwasemployedbyinkmanufacturersintheeighteenthcenturyisshownbytheformulasappearingintheliteratureofthattime。

Itwasusedaloneasaninklongbefore，aswellascontemporaneouslywith，thoseofthetanno-gallateofironfamily。Itslastingpropertiesaremostremarkableifitbetruethat，usedasadye，thereisstillinexistencespecimensofitonclothfivethousandormoreyearsold。ThehistoryofitsuseALONEasaninkisdifficulttoascertainbackofacertainperiod；

thewriterhasseveralspecimensofit，onewrittenin1692whosecolorisagreenblue；anotherwrittenaboutacenturyagoisbelievedtobeasbrightblueasthedayitwasplacedonthepaper；from1810to1850itwasincommonuseparticularlyinhotclimateswhereitwas“home-made。”Consequentlyiftheold“gall“inkscontainedalastingaddedcolor，indigomusthavebeentheone，Dr。Starkwhoseinvestigationsalongthislinefortwenty-threeyearshavealreadybeencitedhassaidthathepreferredforhisownuseaninkcomposedofgalls，sulphateofindigoandcopperas(sulphateofiron)；

thismeansatanno-gallateofironinkwithindigofor“added“color。LikeformulascallingfordifferentproportionsofconstituentsbothbeforeandafterhistimeinEnglandandthecontinentsofEuropeandAmericaaretobefoundinconsiderablenumber，provingthatitsusewasmoreorlessconstantinthisrespect。Todetermine，then，whetherornottheblackerspecimensoftheancientwritingscontainedindigoinanyofitsformswasmostimportant，andtheplanadoptedmostsimple。Specimensofwritingininkofwhichthemanufacturer’snamewasknownaswellashisformulaandonlythirtyyearsoldshowedevidenceofconsiderable“browning；“someofthemwhentestedinjuxtapositionwiththoseoffromfiftytoonehundredyearsoldwhichhadturnedcompletelybrown，gaveapproximatelythesameresults，anddifferentiatedlargelyfromtheresultsobtainedfromjetblackspecimensofeightytofivehundredormoreyearsofage。Inanumberofthebrowneronesindigowasfoundtobepresentwhileinmanyoftheblackonesitwasnot，demonstratingthatthereasonforthecontinuingblacknessoftheolderinksisnotduetoanaddedcolororpigmentofanykindandfurthermorethatthe“Stark“andcorrespondinginkformulasafterthetestofTIMEdidnotretaintheiroriginalblacknessbutdeterioratedtoabrowncolor；moreover，thattheirpurposeasinthepresentdaywastogiveanagreeableandimmediatecolorresult，afree-flowingink，andtocheapenthecostofmanufacturewhencomparedwiththatofanunadulteratedtanno-gallateofironink。

Nodisagreementbeingnowpossibleastothelastingcolorvirtuesofaproperlyproportionedtanno-

gallateofironinkWITHOUTan“added“colororpigment，thereremainedthesolequestionastothevehicleutilizedtoholdthiscombinationinsuspensionandwhetherornotithadtodowiththecontinuingblacknessoftheolderinks。

Theanswermustliebetweenthevegetableproductknownasgumandtheanimalproductknownasgelatine。Thefirstdisintegrates，quicklyabsorbsmoistureandgraduallydisappears，whilegelatine(isinglass)“containsunderconditions50%carbon，althoughitsmolecularformulahasnotyetbeendetermined。Itcannotbeconvertedintovaporanddoesnotformwell-definedcompoundswithotherbodies；itisinsolubleinalcoholwhichprecipitatesitinflakesfromitsaqueoussolution。Itisalsoprecipitatedbytannin，whichcombineswithittoformaninsolublenon-putresciblecompound。Gallicacid，however，doesnotprecipitateit。”(Bloxam。)

Possessinganundisturbedandcompletehistoryitwastheverysubstanceemployedlongbeforethediscoveryofgallink，andisfoundpresentintheearliestspecimensofthe“Indian“inkswhichremaintous。

Itmustnowbeevidentthattherecanbenomaterialdifferenceofopinionsastowhathasbeensoclearlyandconclusivelyestablished，viz。thatinkwhichcontainsabaseoftanno-gallateofiron(without“added“color)isapermanentink，andthelengthofitsdurabilityandcontinuingpristinenesscanbedisturbedonlybyinferiorqualityofconstituents，wrongmethodsofadmixtureanditsfutureenvironment。Henceanyblackinkwiththiscombinationmissingisofnopracticalvaluewhatevereitherforrecordorcommercialuses。

“Indian“ink，exceptforspecificpurposes，belongstothegreatpastandwillsocontinuewithitsvirtuesunchallengedandproven，untilsomesolventisdiscoveredforthecarbonwhichformsnearlythewholeofitscomposition，atwhichtimeTHEperfectinkcanbesaidtohavebeendiscovered。

CHAPTERXVII。

INKPHENOMENA。

CONDITIONOFINKWHENFIRSTPLACEDONPAPER——ITS

METAMORPHOSISANDAFFINITIES——IGNORANCEOFTHE

FORGERASTOITSORIGINALENVIRONMENT——TREATMENT

OFOLDINKMARKS——HOWPAPERMAYDISCOLOR

INK——THEUSESOFACIDININK——VEHICLES

TOHOLDINKPARTICLESANDPRESERVETHEM——INKS

FIVECENTURIESOLDDOPRESERVETHEIR

GLOSS——SOMECAUSESOFINKDISINTEGRATION——WHEN

INKBECOMESIRRESPONSIVETOTHEELEMENTS——

DEMONSTRATEDTRUTHSABOUTINKCONSTITUENTSAND

COLORPHENOMENA——NATURALEVOLUTIONOFAN

INKMARK——LENGTHOFTIMEREQUIREDTOBECOME

BLACK——FIRSTINDICATIONSOFAGE——DISAPPEARANCE

OFINKQUALITIES——ARTIFICIALAGINGOFINK——TESTS

FORITANDHOWTOCONFIRMTHEM——BLEACHINGAND

REMOVALOFINKFROMPAPERCRIMINALLYCONSIDERED——

CHEMISTRYOFSUCHMARKS——THEIRRESTORATION——

VARIATIONSINMETHODSWHICHCANBE

EMPLOYED。

ALLinkswhenfirstplacedonpaperareofcourseinafluidstate。Gradualevaporationofmoisturecausesachangenotonlyincolorbutinthecaseoftheironandgallinks，intheirchemicalconstitution，beingimmediatelyaffectedbytheirenvironment，whetherduetothecharacterofthepaperonwhichtheyrest，thekindorconditionofthepenused，ormostimportantofall，theelements。Thosewhousetheblackinksandchemicalwritingfluidswillhavenoticedthesecharacteristics。Thepalebrown，blueorgreenasfirstwritten，andthegradualchangeafterashortperiodtoanapproachingblackness，arereactionsduelargelytoatmosphericconditions，theoxygenunitingwiththatforwhichithasaffinityandinstantlybeginningwithTIMEtomakeitsmarch，producingnaturalphenomena，whichcanbeonlysuperficiallyimitatedbutneverexactlyreproduced。WhenwefurthertakeintoconsiderationthattheforgercannotalwaysknowofthecircumstanceswhichsurroundtheplacingoforiginalinkonpaperandthatbecannotmanufacturetheTIMEwhichhasalreadyelapsed，itisnotstrangethatattemptedfraudcanoftenbemadeevidentandcompletedemonstrationsgivenofthemethodsemployed。

Withthepassageoftime，theparticlesinsomeinkswhichareheldtogetheronthepaperbygummyvehicles，commencetodisintegrateandchangefromintenseblacktothebrowncolorofironrust，the“added“colorwhichofitselfisfugitiveincharacter，soondeparts；thevegetableastringentseparatingfromtheironsaltdecaysgraduallyanddisappearsandfinallyterminatesinamerestainordustmarkwhichcanbeblownoffthepaper。Sometimes，thewrittensurfaceofsuchpapercanbetreatedbycarefullymoisteningitwithadecoctionofnut-gallsoritsequivalentinthepresenceofaweakacid，thenifanyironbepresent，ameasurabledegreeofrestorationofcolorwillensueandremainforashortperiod。

Again，thediscolorationofanironinkmaybeduetothecharacterofthepaper；ifofthecheapergradesandthebleachingcompoundsemployedintheirmanufacturearenotthoroughlywashedout，thentheinknotonlybeginstoabsorboxygenfromtheatmospherebutthechlorineinthepaperattacksitandtheprocessofdestructionistherebyhastened。

Theintroductionofacidintoinkhastwopurposes，onetosecuremorelimpidity，andtheothertocauseittopenetratethepaperandinthiswaybindtogethertheconstituentparticlesofbothinkandpaper。Mostofthechemicalwritingfluidsofthisdecadecarryasuperabundanceofacidintheircomposition，whichintimewillburnthroughthepaperandultimatelydestroyit。

Alltanno-gallateofironinksrequiresomevehicletoholdtheirparticlesinastateofsuspension，otherwisetherewouldbeprecipitationandsuchaninkcouldnotbeused。Tomeetthisrequirementavarietyofgumsareemployedbymanufacturers，gumacaciabeingtheprincipalone。Itspurposeisthreefold——asbeforestated，toholdtheinkparticlesinsuspension——topreventtheinkfromflowingtoorapidly，andafterdryingWITHOUTblotting，toactasanenvelopetoencasethenowfixedinkandpreventorinterferewithitsabsorptionofanexcessofoxygen。

Thelongertheselatterconditionsobtainthelongerwilltheinkretainitspristineness，itsdurabilityandpermanence。The“timeproved“ink-writtenspecimensoffivehundredyearsormoreagowhichcontinuetoretaintheiroriginalintenseblackcolorand“glossy“appearance，donot，however，yieldanyevidenceoftheuseofvegetablegumsintheircomposition。

Wheresuchinstanceshavebeennoticedtheglossisinvariablymissing。But，whereANYglossispresent，itwasandisbecauseoftheemploymentofisinglass(fish-glue)asthevehicletoholdtheancientinkparticles。

Hencethevariationsofcolorseeninancientpaperwritings，asalreadystated，wereduenotonlytopossibleimperfectadmixturesofthecomponentpartsoftheinks，buttotheuseofvegetablegumsintheirpreparation。Inthecourseoftimethesehavebeenabsorbedbymoisturewhichhasteneddisintegration，causingagradualdisappearanceoftheiroriginalblacknessandglossandfinallyareturntotherustycolorofoxidizediron。

Itthereforefollows，myobservationsanddeductionsbeingcorrect，theolderawritingmadewithtanno-gallateofironink，whereisinglassisthebinder，andwhichhasnotbeen“blotted。”theharderandmoreimperviousandirresponsiveitbecomestotheactionofthenaturalelementsorofchemicalreagents。

Thetruthsdemonstratedinthispropositioncannotbedenied。Theyfortifyascertainthataproperlyproportionedmixtureinwaterofaninfusionofnut-

gallsorgallo-tannicacidandsulphateofiron，withisinglassasthevehicletoboldtheparticlesinastateofsuspension，ifwrittenwithongoodpaperandallowedtodrywithoutblotting，inashorttimebecomesencasedorenvelopedinsuchvehicle，whichistherebyrenderedsubstantiallyinsolubleandabsolutelypreventsanyextensiveoxidation。Also，asafurtherconsequentresult，thereischemicallycreatedanunchangeableandcontinuingblackcolormorepermanentanddurablethanthesubstanceonwhichitappears。

Withasampleofstandardcommercialchemicalwritingfluid，writeon“linen“paperwithoutblottingit；inthirtyhours，ifexposedtotheairandfromthreetofivedaysifkeptfromit，thewritingshouldhaveassumedacolorborderingonblack；itbecomesblackattheendofamonthunderanyconditions，andsocontinuesforaperiodofaboutfiveorsixyears，whenifexaminedunderalensofthemagnificationoftendiameters，therewillbeanoticeablediscolorationofthesidesorpentrackswhichslowlyspreadsduringacontinuingperiodoffromtentofifteenyears，untiltheentirepenmarksareofarustybrowntint。Aspeciesofdisintegrationanddecayisnowprogressingandwhenapproximatelyfortyyearsofage，hasdestroyedallinkqualities。

If，however，“chemicalwritingfluid“isfirsttreatedbyexposuretothefumesofanammoniacalgas，a“browning“oftheinkoccurs，notonlyofthepentracksbutoftheentireinkmark。Ifexaminednowwithalens，theinkisfoundtobethinenoughtopermitthefibreofthepapertobeseenthroughit，thusindicatingartificialage。Furthermore，ifa20percentstrengthofhydrochloricacidbeapplied，the“added“

color(usuallyablueone)isrestoredtoITSoriginalhue；alikeexperimenton“time“agedinkgivesonlytheyellowbrowntintofpuregallandironcombinations，the“added“colorhavingdepartedcausedbyitsfugitivecharacteristics。Again，ifasolutionofchlorinateoflimeorsodabeapplied，theinkmarkisinstantlybleached，whereinthecaseofhonestoldinkmarks，ittakesconsiderabletimetoevenapproximatealikeresult。

Toconfirmthechemicaltestswhichmaybeemployedinthedeterminationoftheartificialagingofinkmarks，photographsmadebypermittinglighttotransmitthroughthepaperandtointerferewithitsraysbyfilteringthemthrougha“color“screencontainingorangeandsomegreen，willindicatethepresenceofafugitivesubstanceintheink，usuallythe“added“coloremployedinitsmanufacture。

Theprocessofbleachingor“removal“ofinkmarksfrompaperisfrequentlyemployedintheattemptederadicationofwordsorfiguresandthesubstitutionofothersonmonetaryinstruments，commonlycalled“raising。”Itspurposeisusuallyacriminaloneandsomeobservationsastothemodusoperandianditschemistryarenotoutofplacehere。

Inkmarksmadewithacompoundconsistingofthecombinationofironandaninfusionofgallsoritsequivalent(atanno-gallateofironink)，astreatedwithcertainchemicals，changefromacompoundwithcolortoachemicalcompound，withnocolor。Nothinghasinfactbeenabsolutelyremovedoreradicated，butitisamerechangeofform，asortofre-arrangementoftheparticles，theingredientswhichformedtheoriginalcolorbeingstillpresent，butinsuchaconditionthattheyareinvisibletotheeye。Arestorationoftheinvisibleinkmarkssothattheycanbeobserved，becomespossiblebytheuseofchemicalreagentsandisthereverseoftheoneoferasureorbleaching，andchangestheconstituentsagainintoacompoundwhichhascolorfromtheonewhichhadnone。Itdoes，not，however，reproducetheexactcompositionoriginallyexisting。Suchareagentsimplygoestothebasisofthematerialasfirstused，takesupwhatwasleftandreformstheparticlessufficientlytomakethemabundantlyrecognizable。Anaptillustrationofthesechemicalchangesofcolorisfoundinwhatisknownasthephenolphtaleintestsolution，whichiscoloreddeeppurplish-redbyalkalihydratesorcarbonates，andthenbytheadditionofanacidrenderedcolorless，tobeagainreddenedbyanover-

plusofthealkaliandsoonadinfinitum。

Apopularmaterialforthepurposeofmakingchemicalerasuresischlorinatedlimeorsoda，whichbecomesmoreactivebyfirsttouchingtheinkmarktoberemovedwithaonehalfstrengthsolutionofaceticacid；thishastenstheliberationofchlorinegas，THEactiveagentwhichcausesthe“bleaching“

totakeplace。Hydrogenperoxide，alsoableachingcompound，islessrapidinitsactionthanchlorinateofsoda；thesamemaybesaidofcombinationsofoxalicandsulphurousacids。

Themosteffectivere-agentfortherestorationofachemically“bleached“ironinkmarkisthesulphideorsulphuretofammonia(ithasseveralnames)。Thispenetratingchemicalblackensmetalsortheirsalts，whethervisibleornot，ifbroughttogether。Itmustnotbeusedbydirectcontact，thebestandsafestplanbeingtoplaceaquantityinasmallsaucer，tobesetonthefloorofaclosedbox；tofastentotheboxlidthespecimentobeoperatedon；inthiswaytherestorationisduetothefumesofthechemicalandapossibledangerofdestructionofthespecimenmuchlessened，especiallyifthemarksareverylightordelicateones。Therestorationofcolorunderparticularconditionsmayalsobeobtainedbytreatmentwithtannicacid，potassiumferro-cyanide(acidulated)oraweaksolutionofaninfusionofgalls。

CHAPTERXVIII。

INKCHEMISTRY。

SOMEOBSERVATIONSASTOCHEMICALEXAMINATIONOF

INKMARKSBYALLEN——ERASINGOFINKSBYCHEMICAL

MEANS——APPROVEDCHEMICALTESTSINTHE

ASCERTAINMENTOFINKCONSTITUENTS。

ACOMPILATIONofthemethodsofRobertson，W。Thompson(LordKelvin)，Irvine，Wislar，Hoffmanandothers，relativetothechemicalexaminationofinkmarks，istobefoundin“Allen’sCommercialOrganicAnalysis。”Theirexperiments，however，datebackmanyyearsago，afewofthembeforethetimeoftheuseofthe“anilines“foraddedcolor。Theso-called“alizarin“inkreferredtohasnowbecomeobsolete。

Thefollowingisthecitationinpart：

“Inchemico-legalcasesitissometimesofimportancetoascertainthenatureoftheinkused，tocompareitwithspecimensofwritingofknownhistory，andtoascertaintherelativeagesofthewritings。Aminuteinspectionshouldfirstbemadewithamagnifyingpowerofabout10diameters，andanypeculiaritiesofcolor，lustre，shade，etc。，dulynoted，andwherelinescrosseachotherwhichlieuppermost。Theexaminationisoftenfacilitatedbymoisteningthepaperwithbenzineorpetroleumspirit，wherebyitisrenderedsemi-

transparent。Theuseofalcoholorwaterisinadmissible。

“Valuableinformationisoftenobtainablebytreatingwritingorotherink-markswithreagents。

Someinksareaffectedmuchmorerapidlythanothers，thoughtherateofchangedependsgreatlyontheageofthewriting。Normaloxalicacid(63

grammesperlitre)，orhydrochloricacidofcorrespondingstrength，shouldbeappliedtoapartoftheinkmarkedwithafeatherorcamel-hairbrush(orthewritingmaybetracedoverwithaquillpen)，andtheactionobservedbymeansofalens，thereagentbeingallowedtodryonthepaper。

Recentwriting(oneortwodaysold)ingallicinksischangedbyoneapplicationofoxalicacidtoalightgray，orbyhydrochloricacidtoyellow。

Olderstainsresistlonger，inproportiontotheirage，andadeepercolorremains。Log-woodinkmarksaremostlyreddenedbyoxalicacid，andalizarinmarksbecomebluish，butanilineinksareunaffected。Withhydrochloricacid，logwoodinkmarksturnreddishorreddish-gray，alizarinmarksgreenish，andanilineinkmarksreddishorbrownish-gray。Thetreatmentwithacidshouldbefollowedbyexposuretoammoniavapors，orblottingpaperwetwithammoniamaybeapplied。

Thustreated，marksinlogwoodinkturndarkvioletorviolet-black。Theageofinkmarksverygreatlyaffectstherateoftheirfadingwhentreatedwithdiluteammonia，theoldmarksbeingmorerefractory。Thebehaviorofinkmarkswhentreatedwithsolutionofbleachingpowderisoftencharacteristic，theolderwritingsresistinglonger；

butunlessthereagentbeextremelydilute，writingsofallagesareremovedalmostsimultaneously。

Hydrogenperoxideactsmoreslowlythanbleachingsolution，butgivesmoredefiniteresults。Afterbleachingthemarkbyeitherreagent，theironoftheinkremainsmordantedonthepaper，andthemarkmayberestoredbytreatmentwithadilutesolutionofgalls，tannicacid，oracidulatedferro-

cyanide。Thesamereagentsmaybeusedforrestoringwritingwhichhasbeenfadedfromagealone。

“Wheninkmarkshavebeenerasedordischargedbychemicalmeans，tracesofthetreatmentareoftenrecognizable。Aftereffectingtheerasurethespotisoftenrubbedoverwithapowderedalumorgumsandarac，orcoatedwithgelatinorsize。

Thebleachingagentsmostlikelytohavebeenusedareoxalic，citric，orhydrochloricacid，bleachingpowdersolution，oracidsulphiteofsodium。

Moistenedlitmuspaperwillindicatethepresenceofafreeacid，andinsomecasestreatmentwithammoniafumeswillrestorethecolor。Thepresenceofcalcium，chlorides，orsulphatesinthewaterinwhichthepaperissoakedwillaffordsomeindicationofbleachingpowderorasulphitehavingbeenused。Potassiumferro-cyanidewilldetectanyironremaininginthepaper。Exposuretoiodinevaporoftenaffordsevidenceofchemicaltreatment，andothermethodsofexaminationreadilysuggestthemselves。”

M。Piesse，intheScientificAmerican，isauthorityforamethodofremovingink，foundon“patent“

checkpaper：

“Alternatelywashthepaperwithacamel’s-

hairbrushdippedinasolutionofcyanideofpotassiumandoxalicacid；thenwhentheinkhasdisappearedwashthepaperwithpurewater。”

Inksofthetanno-gallateofironfamily，whethercontaining“added“colorornot，canbemoreorless“erased“bychlorinateoflimeorsoda，inthepresenceofaweakacid。Thesechemicalsdonot，however，materiallyaffecttheprussianblueinks，whichrequiresolutionsofhydrateofpotashorsoda。

Realindigocanberemovedbychloroform，morphineorananilinesalt(indigoandanilinebothowetheirnamestothesamePortuguesesource)，whichpossesstherarepropertyofdissolvingpureindigo。Suchcombination，ifrefractoryinthepresenceofpermanganateofpotashwithsulphuricacid，mustbefollowedbyanapplicationofsulphurousacid。Inlikemanner，inkscomposedofby-productsofcoaltar，canbeeffectivelytreated，whenirradicablewithplainwaterorsoapandwater。

Theerasureandremovalofmostinksfrompapercanbeaccomplishedbytheapplicationofthechemicalsheretoforeenumerated。Therequirementsinthisdirectionofsomeinks，however，thoughofrareoccurrence，aretobemetbytheemploymentofotherandparticularreagents。

ManyofthetestsspecifiedintheAllencitationtodeterminethecharacterofinkconstituents，ifmadealonearepracticallyvalueless，becausethesamebehavioroccurswithdifferentmaterialsemployedintheadmixtureofink。Toavoiderrorinjudgmenttheoperatorshouldverifyifpossiblebyconfirmatorytests。Thus，intheoneforlogwood，sulphurousacidwillcausealogwoodinkmarktoturnyellow；mercuricchloride，orange；tartar-emetic，red；andifthemarksarefadedones，solutionsofsulphateofironorbichromateofpotashwillrestorethemrespectivelytoavioletorblue-blackcolor。

Prussianblue，anilineblueandindigobluearetobetestedasfollows：Solutionofchlorideoflime，nochangeofcolorforprussianblue；decolorationorfaintyellowforanilineblueorindigo。Todiscriminatebetweenthetwolatter，testwithsolutionofcausticsoda，whendecolorationorchangeofcolorwillindicateanilineblueandpermanencewillindicatepresenceofindigoblue。

Inthemanufactureoftheblue-blackinks，avarietyofvioletshavebeenandarestillemployed。Amongthemareanilineviolet，iodineviolet，madder，alkanet，orchilandlogwood。

(a)Applychlorideoflimesolution：1。Nochangeofcolorindicatesalkanet。2。Anychange，oneoftheotherfive。

(b)Applylemonjuice：1。Thevioletbecomesbrighterifitisoneoftheanilineviolets，tobedistinguishedfromeachotherbyapplyingonepartofhydrochloricacidtothreepartsofwater，whenitwillbecomeviolet-blue，changingtoredifitiscommonaniline-violet，butbluechangingtoagreenhueanduponaddingplainwatertoalilacorpearlgrayifitisiodine-violet(Hoffman’s)。Itwillalsoturnfromredtoyellowinlemonjuice。Totestfortheotherthreeviolets：(a)Applychlorideoflime，tobefollowedbyasolutionofyellowprussiateofpotash：

absenceofabluecolorationleavesorchilandlogwoodtobeconsidered。Todistinguishbetweenthemapplysolutionofhydrateoflime，wherebyachangetogray，followedbycompletedecolorationindicateslogwood，andachangetoviolet-blue，orchil。

Thesubstancesutilizedwithbutfewexceptionsforredinkarethe“eosins。”possessingdifferentnameslikeerythrosine，aswellasdifferenthues。Antecedenttoaboutthirty-fiveyearsago，cochineal(knownas“carmine“)，madder，Brazilwoodandsaffronformedthebasisofmostoftheredinks。

Makeasoapsolutionaddingasmallquantityofammonia，lemonjuice，muriateoftin，allinwater：

1。Nochangeuponapplicationindicatesmadder。

2。Anychange，thepresenceofoneofthethreeotherreds：(a)thusacompletedecolorationwithareturnofthecolorindicatessaffron；(b)reappearanceoftheredcolorthoughweaker，aniline-red：(c)productionofayellowishredorlightyellowcolor，cochinealorBrazilwood，tobedistinguishedfromeachotherbytheapplicationofconcentratedsulphuricacid，whenBrazilwoodwillatoncegiveabrightcherry-red，andcochinealayellowishorange。

Noyellowinksareincommercialuse。Documentsdo，however，oftencontainyellowmarksaboutwhichinformationisrequiredastotheirorigin。Asaruletheyareironrust，picricacid，turmeric，fustic，weld，Persianberriesorquercitron。Inordertorecognizethedifferentcolors，thepresenceorabsenceofironrustandpicricacidmustfirstbedetermined。

Applyawarmsampleofaslightlyacidsolutionofyellowprussiateofpotash；ironrustwillbeindicatedbyabluecoloration。

Applyaweaksolutionofcyanideofpotassium；picricacidwillyieldablood-redcoloration。

Ifpicricacidandironrustarebothabsent，applyabitofordinarywettedsoap：1。Itturnsreddish-brownandbecomesyellowagainwithhydrochloricacid——

turmeric；2。Itturnsquitedark——fustic；3。Itisunaffected——weld，Persianberriesorquercitron。Todistinguishbetweenthesethree，applysulphuricacid，thecolorofweldwilldisappear，andoftheothersremainingapplytin-saltsolution，whenachangetoorangeindicatesPersianberries，andnochangeoraveryslightone，quercitron。

Inkscontainingalsologwood，fustic，Brazilwood，ormadder，wereallofthemmoreorlessemployedsomeyearsago。Theircolorphenomena，followinglongperiodsoftime，ismuchthesame。Testsasprescribedintheaccompanyingtableforsuchinkswillservetoclassifythempreliminarytosubsequentandmorecertainones。

LOGWOOD。FUSTIC。

ConcentratedHydrochloricAcidRed-yellowRedDilute““ReddishYellow-BrownConcentratedanddiluteNitricAcidRedRed-Yellow“SulphuricAcid……BlackDarkPurpleDilute““RedBrownPurplePotassiumChromate……BlackStannousChlorideVioletYellowTartaricAcid……Gray-BrownYellowSulphateofCopper……DarkGrayTannin……Yellow-RedYellowPotashDarkRedYellowPotassiumPermanganateLight-BrownYellow“Iodide……Red-YellowPyrogallicAcid……Yellow-BrownYellowChrome-yellow……DarkVioletSodium(Salt)VioletRedSulphateofIronGraytoBlackAlum……VioletRed，Brown。FaintRedBRAZILWOOD。MADDER。

ConcentratedHydrochloricAcidLightRedPaleYellowDilute““LightRedPaleYellowConcentratedanddiluteNitricAcidDarkPurplePaleYellow“SulphuricAcid……RedPaleYellowDilute““PurplePaleYellowPotassiumChromate——

StannousChlorideLightRedLightRedTartaricAcid……RedYellowPaleYellowSulphateofCopper——

Tannin……NoChangePaleYellowPotashCrimsonLightRedPotassiumPermanganate——

Iodide——

PyrogallicAcid——

Chrome-yellow——

Sodium(Salt)-RedSulphateofIronDarkViolet-

Alum-FaintRedCHAPTERXIX。

FRAUDULENTINKBACKGROUNDS。

DETECTIONOFALTERATIONSINDOCUMENTSBYCHEMICAL

TESTSWHICHAPPLYSOLELYTOTHEPAPER——ACCURACY

OFRESULTSOBTAINEDBYUSEOFIODINE

EXCELSTHATOFALLOTHERCHEMICALS——ITAPPLIES

BESTTOLINENPAPER——MODERNHARDPAPERDOES

NOTGIVECOMPLETEINFORMATION——EFFECTOFIODINE

ONMARKSMADEBYASTYLUSORGLASSPEN。

FIFTYyearsagoandlongbeforetheemploymentofthefugitive“anilines“forinkuses，and“woodpulp“asamaterialforpaper，twoFrenchchemists，ChevallierandLassiagne，publishedintheJournaldeChimieMedical，anarticle“OntheMeanstobeEmployedforDetectingandRenderingPerceptibleFraudulentAlterationsinPublicandPrivateDocuments。”

whichastranslatedisvaluableenoughtoquoteinfull：

“Thenumerousexperimentswhichhavebeenalreadytriedatvarioustimes，havemadeknowntheprocesseswhichmayfrequentlybeputinpracticeforcausingthereappearanceoftracesofwritingeffacedbychemicalreactions，andforthrowinglightontheworkoftheguilty。Buttherearecasesinwhichallthemeansproposedforthispurposefail，andthenthecriminalmayescapejusticefromthewantofconclusivematerialproofs。If，ashasalreadybeenproved，itisnotalwayspossibletocausethereappearanceoftheeffacedwriting，forwhichwrittenwordshavewithafraudulentintentbeensubstituted，atleast，asourexperimentsdemonstrates，wemayrecognize，bysomeeffectswhicharemanifestonthesurfaceofthealteredpaper，theplaceswherethecriminalacthasbeenperformed，circumscribethembyasimplechemicalreactionvisibletotheleastpracticedeye，andevenmeasuretheirextent。Inaword，thevisiblealterationsproducedonadeedaresusceptible，owingtothepartialmodificationswhichthesurfaceofthepaperhasundergone，ofbeingdifferentlyaffectedbycertainchemicalactions，andofbeingrenderedvisible。Thefollowingexperiments，madeinajudicialinvestigation，furnishuswiththefollowingfacts：

“1st。Thesurfaceofpapersizedintheordinaryway，orletterpaper，nolongerpresentswithcertainreactions，thesameuniformitywhereithasbeeneitheraccidentlymoistenedinseveralplacesbyvariousliquids，orleftincontactforacertaintimewithagentscapableofremovingordestroyingthecharacterswhichhavebeentracedonitwithink。

“2d。Theapplicationofathinlayerofgum，ofstarch，orfarina，ofgelatine，orfish-glue，withaviewofsizingcertainpartsofthepaper，orofcausingcertainbodiestoadheretoitmomentarily，isdetectedbyanactionsimilartothatwhichshowspapertohavelatelybeenwettedbythecontactofliquids。

“3d。Theheterogeneousnessofthepulpofthepapers，andthekindofsizewithwhichtheyareimpregnated，leadtodifferencesintheresultswhichareobservedwiththesamechemicalreagents。

Weshallnowexamineeachofthesepropositions，anddescribethemeanswhichwehaveemployedinendeavoringtosolvequestionsofsohighadegreeofinterest。

“1st。Thehomogeneousnessofsizedpapernotpartiallyalteredbythecontactofliquids(water，alcohol，salt-water，vinegar，saliva，tears，urine，acidsalts，andalkalinesalts)isdemonstratedbytheuniformcolorationwhichthissurfacetakesonbeingexposed，ifnotwholly，atleastinvariousparts，totheactionofthevaporofiodinedisengagedattheordinarytemperaturefromaflaskcontainingaportionofthemetalloid。Whenthesurfaceofpapernotstainedbyanyoftheabovementionedliquidsisexposedtotheactionofthisvaporforthreeorfourminutesinaroomthetemperatureofwhichisabout60degreesF。，auniformyellowish，orlight-brownishyellow，colorationisnoticedonthewholeextentexposedtothevaporofiodine；inthecontrarycase，thesurfacewhichhasbeenmoistened，andafterwardsdriedintheopenair，isperfectlydistinguishedbyadifferentandwellcircumscribedtint。Onthepapersintowhichpastestarchandresinhavebeenintroduced，thestainspresentsuchdelicatereactionsthatwemaysometimesdistinguishbytheircolortheportionofpaperwhichhasbeenmoistenedwithalcoholfromthatwhichhasbeenmoistenedwithwater。Thestainproducedbyalcoholtakesabistre-yellowtint；thatformedbywateriscoloredofamoreorlessdeepvioletblue，thedesiccationhavingbeeneffectedattheordinarytemperature。Forthestainsoccasionedonthesesamepapersbyotheraqueousliquids，thetint，apartfromitsintensity，resemblesthatofthestainsofpurewater。Thefeebleordiluteacidsactlikewateronthesurfaceofthesamepapercontainingstarchinitspaste；

buttheconcentratedmineralacids，byalteringmoreorlessthesubstanceswhichenterintothecompositionofthelatter，givetesttothestainswhichpresentdifferences。Wearealwaysabletorecognizebytheactionofthevaporofiodinethepartsofthepaperwhichhavebeenputincontactwithchemicalagents，theenergyofwhichhasbeenarrestedbywashingincoldwater。Weareable，onseveralancientdeeds，writtenonstampedpaper，andafewwordsofwhichhadbeenremovedbyuswithchemicalagents，torecognizetheplaceswheretheiractionwasexerted，toseeandtomeasuretheextentwhichtheyoccupiedonthesurfaceofthepaper。

“Thetestingofapaperwiththevaporofiodinewillpresentthisdoubleadvantageoverthemethodshithertopracticedfordetectingfalsificationsinwritings，thatitpointsoutatoncetheplaceinthepaperinwhichanyalterationmaybesuspected，andthat，ontheotherhand，itenablesustoactafterwardswiththereagentsproperforcausingthereappearanceofthetracesofink，whenthatispossible。Ifthemeanswhichwenowproposecannotalwaysmaketheformerwritingappear，theydemonstratetheplaceswherethealterationsmusthavebeenmade，when，however，thewantofuniformitypresentedbythesurfaceofthepaperisnotexplainedbyanycircumstance。

Thisproofbecomes，therefore，aweaponwhichtheguiltypersoncannotavoid。Butmightnotthepresenceofastain，orseveralstains，developedbythevaporofiodine，indifferentpartsofapublicorprivatedeed，giverisetoasuspicion，wherethesestainshave，perhaps，beenoccasionedbythespillingofsomeliquidonthesurfaceofthepaper？

andwoulditnotberashandunjusttoraiseanaccusationfromsuchafact？Therewouldindeedbegreattemerityindrawingsuchaconclusionfromafortuitouscircumstance；buttheinferencewhichmaybedrawnfromtheplaceoccupiedbythesestainsonthesurfaceofthepaper，fromthemoreorlesssignificantwordsfoundinthoseplaces，wouldnotpermitanaccusationtobesolightlybrought，wheresimplereasoningwouldbesufficienttodestroyitsbasis。Besides，thesubsequentreactionswhichwouldbemadewouldcertainlyneverrevivewordsformerlywrittenandeffaced；whilstthelattereffectsmaybeoftenproduced，moreorlessvisibly，onthosepartsofthepaperonwhichfalsificationhasbeenpracticed，figuresorwordsbeingsubstitutedforotherfiguresorwords。

“2d。Theapplicationsmadetothesurfaceofasheetofpaper，withaviewofcoveringitagainatcertainpartswithafinelayerofgum，gelatine，starchorflourpaste，orinotherplacestocauseothersheetsofpapertoadhere，mayberecognizednotonlybythereflectionoflightfallinguponthepaperinclinedatacertaindegreeofobliquity，andbythetransmissionoflightthroughthepaper，butalsobythevaryingactionwhichthevaporofiodineexertsonthesurfacewhichisnothomogeneous。

Paperscontainingstarchandresinaremorepowerfullyacteduponbythisvaporthanpapersofalesscomplexcomposition。Bothinthepartscoveredwithstarch，orpasteflour，arecoloredinafewminutesofavioletblue；butwithstarchedpapersaloneamoreintensecolorationismanifestontheplacescoveredagainwithathinlayerofgumarabic，sizeorgelatine。Bylooking，then，onthesurfaceofthepaper，heldsomewhatobliquelytoincidentallight，wedistinguishclearly，bytheirdifferentaspects，thepartsonwhichthesevarioussubstanceshavebeenapplied。Thevaporofiodine，incondensingattheordinarytemperatureonthesurfaceofthepaperstowhichanykindofsizehasbeenappliedinvariousplaces，producesdifferenceswhicharemostcommonlywellrecognizedbythegreaterorlesstransparenceofthepasteofthepaper。

3d。Theheterogeneousnessofthepulpofthevariouspapersofcommerce，andthenatureofthesizewithwhichtheyarepenetrated，causedifferences，eitherinthecolorationwhichthesurfaceofthesepaperstakeswhenexposedtothevaporofiodine，orinthetintwhichismanifestedintheportionsofthesizedepositedincertainportionsofthatsurface；thus，paperswithstarchedpulpgenerallyturnbrown，orblue，accordingtotheamountofwaterthatremainsintheirinterstices；

otherpapersturnyellowonlyundertheinfluenceofthevaporofiodine，andthepartswhichhavereceivedsuperficiallyalayerofanotheragglutinativebodyresistthisactionforacertaintime，andaredistinguishedfromthepartsofthepaperwhicharenotcoveredwithit。”

Myowninvestigationsconfirmtoagreatextentthevalueoftheseexperimentsandtheaccuracyofthedeductions，insofarastheyrelateto“linen“

paper；buttheydonotalwaysobtainwhenmadeinconnectionwithpaperofinferiorgrades。

Itisalsotruethatdrypaperisaffecteddifferentlyundertheinfluenceofthevaporofiodine，aswouldbepaperwhichhadbeenmoistenedandthendried；

butthepartwhichhadbeenmoistassumesthecolorofblue-violet，whileunalteredpaperassumesayellow-

browncolor。Evenwhenthepaperthustreatedismoistenedalloverwithwater，therewillbeadifference，forthosepartswhichhadbeenbeforemoistened，willappearadarkviolet-blue，whiletheotherpartswillshowaplainbluecoloration。

Incaseswherepencilwritinghasbeenremovedwithasoftrubberorfreshbread，thepartsthuserasedwillassume，whensubjectedtoiodinefumes，abrowncolortrendingtowardsvioletandmuchdarkerthantheundisturbedportionsofthepaper。Linesimpresseduponpaperwitha“stylus。”aglassorordinarydrypen，canbemadevisiblebythefumesofiodine，thelinesshowingwithastrongercolorationthanthesurroundingpaper。

CHAPTERXX。

FUGITIVEINK。

SOMEOBSERVATIONSABOUT“ADDED“COLORTOINK——

INVENTIONOFCOALTARCOLORS——CHRONOLOGICALHISTORY

OFTHE“ANILINES“EMPLOYEDASINK——OTHER

SUBSTANCESUSEDFORTHESAMEPURPOSE。

THEterm“addedcolor。”asappliedtoink，isthepopularphraseologyforamultitudeofmaterialswhichhavebeenmoreorlessutilizedforaperiodofcenturies，inadulteratingandcoloringink。Inoldentimestheywereintroducedintoinkwithanhonestbeliefthatitwouldalsoimproveandensureitslastingqualities，butlatterlymoreoftentocheapenthecostofitsmanufacture。Referencehasbeenmadetoalargevarietyofthesesubstancesusedforthispurposeandthestorytoldoftheeffectofthetestoftimeuponthemasindicativeoftheirsupposedvalue。

Attentionhasalsobeendirectedtothediscoveryduringthenineteenthcenturyofthecolorswhichowetheirorigintoby-productsofcoaltar。

Genericallythesecolorsareclassifiedas“anilines。”

Theyhaveworkedarevolutioninalltheartsinwhichcolorsareused。Employedwithoutamordant，withfewexceptions，theyaremeasurablyaffectedbybothlight，heat，moisture，orotherchangesandasmadeintoinksareneverpermanent。Hencetheyshouldnotbeusedforrecords，becauseifobliteratedfromanycausewhatever，therearenoknownmeanstorenderthemagainlegible。

Theoriginandhistoryofthe“anilines“areknown。Viewedfromaninkstandpointtheyareofvastinterest。Soextendedinnumberarethe“anilines“

(theyrunintothethousands)thattheyincludeeveryshadeofblackandallpossibletintsorhuesofthecolorsoftherainbow。

Thechronologicalhistoryofsuchoftheseartificialcolorswhichappertaintoinkoritsmanufactureisimportantaslocatingthedatesoftheirinventionandcommercialuse。

Thefirstdiscoveryof“aniline“iscreditedtoHelotin1750。In1825Faradayinrectifyingnaphthadiscoveredbenzole，whichbytheactionofstrongnitricacidbeconvertedintonitro-benzole；andthislatter，whenagitatedwithwater，aceticacidandironfilingsproducedaniline。Unverdorbenin1826discoveredananalogousmaterialinproductsobtainedbythedestructivedistillationofindigo。Rungein1834claimstohavedetecteditincoaltarandcalleditkyanol，whichafteroxidationbecameaninsolubleblackpigmentandknownasanilineblack。Itcouldnot，however，beusedasanink。Zinanin1840，experimentingalongthesamelines，producedanothercompoundtermingitbenzidam。Fritscheinthesameyearbythedistillationofindigowithcausticpotashdevelopedaproductwhichhealsocalledaniline，thenamebeingderivedfromthePortuguesewordanil，meaningindigo。ShortlyafterwardsA。W。Hoffmanestablishedtheidentityofthesesubstances。

Anilinewhenpureisacolorlessliquid，possessingaratherammoniacalodor。Itsoonbecomesyellowandyellow-brownundertheinfluenceoflightandair。

Itdoesnotaffectlitmuspaper。

In1856Perkinsaccidentallydiscoveredthevioletdyecalledmauve，whichacquiredconsiderablecommercialimportancebesidesitsutilityforinkpurposes。

Nicholsonin1862succeededinproducingthefirstofthesolubleblueanilines。

Thediscoveryofinduline，oneofthemodificationsofanilineblack，wasmadeknownin1864。

Nigrosine，producedbytheactionofconcentratedsulphuricacidontheinsolubleindulines，wasdiscoveredin1868。

Thesolubleindulinesandnigrosinesdifferentiateinappearance，thefirstabronzypowderandthelatterablacklustrouspowder。Whenmadeintoinktheypossessaboutequalcolorvalues。

In1870theGermanchemists，GraebeandLiebermann，announcedthattheyhadsucceededinproducingartificialalizarin，——thecoloringmatterofthemadderroot。Commercialvaluewasnotgiventothisdiscoveryuntilitwasputonthemarketin1873，althoughitdidnotmeetalltherequirements。

Springmuhlin1873obtainedanaccessoryproductintheartificialmanufactureofalizarinoutofanthracene，fromwhichabeautifulbluewasmade，superiorinmanyrespecttotheanilineblues。Itdifferedfromanilineinhavingthesamecolorinsolution。Alkalisdestroyedthecolorbutacidsrestoredit。Theprocesswaskeptasecretforalongtime。Thisproductwasoriginallysoldashighas$1，500forasinglepound。

Caro，aGermanchemist，inventedin1874theredcolorknownaseosine，whichwasbroughttothiscountryinthefollowingyearandsoldfor$125perpound。Itscolorisdestroyedbyacids。

Orchilorarchil(theredcolor)wasdiscoveredin1879。Thecommercialuseoftheso-called“orchilsubstitutes“(purples)began，however，intheyears1885and1887。

Artificialindigo，astheresultofmanyyearsofexperimenting，cameintocommercialuseunderthenameof“indigopure“onlyin1897。Ithadpreviouslybeenproducedsyntheticallyinavarietyofways，butthecostoftheproductionwasfarabovethatofthenaturalproduct。BaeyerandEmmerlingin1870，Suidain1878，Baeyerin1878，BaeyerandDrewsenin1882，andHeumannin1890，canbesaidtohavebeenthepioneersintheproductionofartificialindigo。

Theintensityofsomeoftheanilinecolorsmaybeindicatedbythefactthatasinglegrainofeosineintenmillionsofwaterexhibitsadefiniterose-pinkcolor。

Itisassertedthatinthelastthreeyearsmanyimprovementshavebeenmadeinthepermanentqualitiesofsomeofthesolubleanilines，butnomaterialwhichissolubleinplainwatershouldeverbeemployedasaninkforrecordpurposes。

Precedingthediscoveryofthe“anilines。”asalreadyrelated，othersubstanceshadbeenemployedfor“added“colorintheadmixtureofink，principallymadder，Brazilwood，indigo，andlogwood。

OnlyacasualreferencehasheretoforebeenmadetoBrazilwoodandlogwood。

Brazilwood，alsocalledpeachwood，isimportedfromBrazil。Itsemploymentasadyestuffisknowntobeofgreatantiquity，antedatingconsiderablythediscoveryofSouthAmerica。Bancroftstates，“Thename’Brazil’wasgiventothecountryonaccountoftheextensiveforestsofthealreadywell-known’Brazilwood，’whichwasfoundbyitsPortuguesediscoverers。Thedyestuffthusgaveitsnametothecountryfromwhichitwasafterwardsprincipallyobtained。Theword’Brazil’appearstohavebeenoriginallyusedtodesignateabrightredorflamecolor。ThusinacontractbetweenthecitiesofBolognaandFerrara，in1194，thedyestuffkermezisreferredtoasgranadeBrazileandBrazilwood，bothdyestuffsatthattimebeingobtainedfromIndia。”

For“added“colortoinkandaloneitwasmuchusedintheseventeenthandeighteenthcenturies。

Logwood，employedmoreextensivelyfor“added“

colorthananyothercolorcompound，wasintroducedintoEuropebytheSpaniards，A。D。1502。InEnglanditdoesnotappeartohavebeenmuchuseduntilabout1575。In1581theParliamentprohibiteditsuse“becausethecoloursproducedfromitwereofafugaciouscharacter。”Itsusewaslegalizedin1673

byanact，thepreambleofwhichreads，“TheingeniousindustryofmoderntimeshathtaughtthedyersofEnglandtheartoffixing，thecoloursmadeoflogwood，aliasblackwood，soasthat，byexperience，theyarefoundaslastingasthecoloursmadewithanysortofdyeingwoodwhatever。”ItisobtainedprincipallyfromtheCampeachytree，whichgrowsintheWestIndiesandSouthAmerica。

ThepracticalutilityoflogwoodasthebaseforaninkwasadiscoveryofRungein1848，whofoundthatadilutesolutionofitscoloringmatter，towhichhadbeenaddedasmallquantityofneutralchromateofpotassium，producedadeepblackliquidwhichapparentlyremainedclearanddidnotdepositanysediment。

Thiscompositionbecameverypopularonaccountofitscheapnessanddarkpurplecolor。Itisofafugitivecharacter，though，andhaspassedalmostentirelyoutofcommercialuse。

CHAPTERXXI。

ANCIENTANDMODERNINKRECEIPTS。

“INDIAN“INK——SPANISHLICORICE——BITUMEN——CARBON

FROMPETROLEUM——PROCESSTOOBTAINGALLIC

ACID——EFFECTOFSUGARININK——DARKCOLORED

GALLSBESTFORINKMAKING——SUBSTITUTESFOR

GALLS——RELATIVEPROPORTIONSOFIRONAND

GALLS——ANECDOTEOFPROFESSORTRIALL——

ESTIMATIONOFSULPHATEOFCOPPER——QUAINTINK

RECIPE——RIBAUCOURT’SINK——HORSELEY’SINK——

ELSNER’SINDELIBLEMARKINGINK——BLACKINKFOR

COMMONANDCOPYINGUSES——COMMONBLACK

INK——SHININGBLACKINK——PROCESSFOR“BEST“

INK——INDELIBLEBLACKINKWITHOUTGALLSOR

IRON——INKPOWDER——STEELPENINK——SOMEEARLY

LITERATUREOFTHECOALTARPRODUCTS——INKPLANT

OFNEWGRANADA——“IMPERISHABLE“INK——FIRE-

PROOFINK——“INERADICABLE“INK——EXCHEQUER

INK——“PERMANENT“REDINK——SUBSTITUTEFOR“INDIAN“

INK——TOPREVENTINKFREEZING——BACTERIA

ININK——GOLDANDOTHERINKSUSEDFORILLUMlNATING。

INNUMERABLEreceiptsanddirectionsformakinginksofeverykind，colorandqualityaretobefounddistributedinbooksmoreorlessdevotedtosuchsubjects，intheencyclopaedias，chemistries，andotherscientificpublications。Ifassembledtogethertheywouldoccupyhundredsofpages。Thosecitedareexemplarsindicatingthetrendofideasbelongingtodifferentnations，epochs，andthediversityofmaterials。Theycanalsobeconsideredasobjectlessonswhichconclusivelydemonstratethedissatisfactionalwaysexistinginrespecttotheconstitutionandmodesofinkadmixture。

Manyofthemarecuriousandarereproducedwithoutanyamendments。

“IndianinkisablackpigmentbroughthitherfromChina，whichonbeingrubbedwithwater，dissolves；andformsasubstanceresemblingink；

butofaconsistenceextremelywelladaptedtotheworkingwithapencil-brush，onwhichaccountitisnotonlymuchusedasablackcolourinminiaturepainting；butistheblacknowgenerallymadeuseofforallsmallerdrawingsinchiaroobscuro(orwheretheeffectistobeproducedfromlightandshadeonly)。

“ThepreparationofIndianink，aswellasoftheothercompositionsusedbytheChineseaspaints，isnothithertorevealedonanygoodauthority；

butitappearsclearlyfromexperimentstobethecoaloffishbones，orsomeothervegetablesubstance，mixedwithisinglasssize，orothersize；andmostprobably，honeyorsugarcandytopreventitscracking。Asubstance，therefore，muchofthesamenature，andapplicabletothesamepurposes，maybeformedinthefollowingmanner。

“Takeofisinglasssixounces，reduceittoasize，bydissolvingitoverthefireindoubleitsweightofwater。TakethenofSpanishliquoriceoneounce；anddissolveitalsoindoubleitsweightofwater；andgrindupwithitanounceofivoryblack。Addthismixturetothesizewhilehot；

andstirthewholetogethertillalltheingredientsbethoroughlyincorporated。Thenevaporateawaythewaterinbalenomariae，andcasttheremainingcompositionintoleadenmoldsgreased；ormakeitupinanyotherform。”

“ThecolourofthiscompositionwillbeequallygoodwiththatoftheIndianink：theisinglasssize，mixtwiththecolours，workswiththepencilequallywellwiththeIndianink；andtheSpanishliquoricewillbothrenderiteasilydissolvableontherubbingwithwater，towhichtheisinglassaloneissomewhatreluctant；andalsopreventitscrackingandpeelingofffromthegroundonwhichitislaid。”

*******

ThereisfoundinsmallcurrentsneartheBaltickSea，intheDutchyofPrussiaacertaincoagulatedbitumen，which，becauseitseemstobeajuiceoftheearthiscalledsuccinum；andcarabe，becauseitwillattractstraws；itislikewisecalledelectrum，glessum，anthracitrina，vulgarlyyellowamber。

“Thisbitumenbeingsoftandviscous，severallittleanimals，suchasflies，andants，dosticktoit，andareburiedinit。

“Amberisofdifferentcolours，suchaswhite，yellowandblack。

“Thewhiteisheldingreatestesteeminphysick，tho’itbeopacous；whenitisrubbedagainstanything，itisodoriferous，andityieldsmorevolatilesaltthantherest。Theyellow，istransparentandpleasanttotheeye，whereforebeads，necklaces，andotherlittleconceitsaremadeofit。Itisalsoesteemedmedicinal，andityieldethmuchoil。

“Theblackisofleastuseofall。(Sometimesusedbytheancientsinmakingink。)

“Somedothinkthatpetroleum，orOilofPeter，isaliquordrawnfromamber，bythemeansofsubterreneanfires，whichmakeadistillationofit，andthatjet，andcoalsaretheremaindersofthisdistillation。

“Thisopinionwouldhaveprobabilityenoughinit，iftheplaces，fromwhencethissortofdroguesdoescome，werenotsofarasundertheonefromtheother；forpetroleumisnotcommonlyfoundbutinItaly，inSicily，andProvence。Thisoildistilsthroughthecleftsofrocks，anditisverylikelytobetheoilofsomebitumen，whichthesubterraneanfireshaveraised。”

*******

Therearevariousprocessesforobtaininggallicacid，oneofwhichistomoistenthebruisedgallsandexposethemforfourorfiveweekstoatemperatureof80degreesFahr。；bywhichamouldypasteisformed，whichispresseddryandthendigestedinboilingwater，whichafterevaporationyieldstheacid，andmixedwiththesolutionofgreencopperas，makesthe，ink。Aquickerprocess，however，istoputthebruisedgallsintoacylindricalcopperofadepthequaltoitsdiameter，andboiltheminninegallonsofwater——takingcaretoreplacethewaterlostbyevaporation。Thedecoctiontobeemptiedintoatub，allowedtosettle，andtheclearliquidbeingdrawnoff，theleesareemptiedintoanothertubtobedrained。Thegreencopperasmustbeseparatelydissolvedinwater，andthenmixedwiththedecoctionofthegalls。A

precipitateisthenformedinthestateofafineblackpowder，thesubsidenceofwhichispreventedbytheadditionofthegum，which，separatelydissolvedinasmallquantityofhotwater，combineswiththeclearblackliquid。Besidesitseffectinkeepingthefineinsolubleparticlesinsuspension，thegummucilageimprovesthebodyoftheink，preventsitsspreadingorsinkingtoomuchintothepaperinwriting，andalsoactsbeneficiallybyformingasortofcompactvarnishinit，whichtendstopreserveitscolour，andshielditfromtheactionoftheair。If，however，toomuchmucilageisused，theinkflowsbadlyfromquillpens，andstillmoresofromsteelpens，whichrequireaverylimpidink。Theadditionofsugarincreasesthefluidityofink，andpermitsthequantityofgumtobeincreasedoverwhatitwouldbearwithoutit；

but，ontheotherhand，itcausesittodrymoreslowly，andbesidesitfrequentlypassesintovinegar，whenitactsinjuriouslyonthepens。Thedark-

colouredgalls，knownastheblueAleppoones，aresaidbyRibaucourt，andotherswhohavegivenmuchattentiontotheingredientsforink-makingtobethebestforthatpurpose，andtheyaregenerallyusedbythebestmakers。

“Fromtheirhighprice，however，andthatofgallsgenerally，sumach，logwood，andevenoakbarkaretoofrequentlysubstitutedinthemanufactureofinks，butitneedscarcelybesaidalwaysinjuriously。Inkmadeaccordingtothereceiptgivenaboveismuchmorerichandpowerfulthanmanyofthosecommonlymade。Toreduceittotheirstandardonehalfmorewatermaybesafelyadded；oreventwentygallonsoftolerableinkmaybemadefromthesameweightofmaterials。

Sumachandlogwoodadmitofonlyaboutone-halforlessofthegreencopperasthatgallswilltake，tobringoutthemaximumamountofblackcolour。

Thecolourofblackinkgraduallydarkensinconsequenceoftheperoxidationoftheironinitonexposuretotheair，butitaffordsamoredurablewritingwhenusedpale；itsparticlesbeingthenfiner，penetratethepapermoreintimately，andonitsoxidationismordantedintoit。Itisadvisablesosoonastheinkhasacquiredamoderatelydeeptint，todrawitoffclearintobottlesandcorkthemwell。

“Accordingtothemostaccurateexperimentsonthepreparationofblackwritinginks，itappearsthattheproportionofthegreencopperasoughttobe，andnottoexceed，athirdofthedecoctionofgallsused；buttheproportionsusedvaryaccordingtothepracticalexperienceofink-makers，whohaveallreceiptsoftheirown，whichtheydeembest，and，ofcourse，keepsecret。Intheprecipitateanexcessofcolouringmatter，whichisnecessaryforitsdurability，ispreservedinit。Thebluegallsaloneoughttobeemployedinmakingthebestqualityofblackink。Logwoodisauseful。

ingredient，becauseitscolouringmatteruniteswiththesulphateofironandrendersitnotonlyofaverydarkcolour，butalsolesscapableofchangefromtheactionofacidsoroftheatmosphere。

Manyattemptshavebeenmadebyamateurstomakeagoodpermanentblackink。AgoodstoryistoldofProfessorTraill。Hehadsucceeded，afteralongseriesofexperiments，inproducinganinkwhichhedeemedtobeinallrespectsA1，andwhichresistedtheactionofallacidsandalkaliesalike。Thepleasedsavantsentsamplesofitfortrialtoseveralbanksandschools，whereitgavegeneralsatisfaction；but，alas，anexperimentingscribbler，thoughtlesslyorotherwise，appliedasimpletestundreamtofbytheProfessor，andwithawetspongecompletelywashedoffhis’indelible，’andtherebyfinishedhiscareerasanamateurink-maker！“

*******

“Nicholson，inhisDictionaryofChemistry，anoldbutvaluablework，saysthatRibaucourtfoundvitriolofcopper，inacertainproportion，togivedepthandfirmnesstothecolourofblackink；

but，fromwhatevercause，thishasnottakenaplaceamongthecommonly-usedink-makingingredients——

probablybecauseitactsinjuriouslyonsteelpens。”

*******

“AquartofrainWate。3OuncesofBlueKnollyGawalls。Bruiseymitmuststand&bestirred3or4timesinymDay&thenStrainoutoutallyegawellsalltenDaysand2OuncesofClearGummaryBeck&1/2anOunceofCoperous1/2anOunceofRockAlumhalfanOunceofLoafesugaryeBignessofaHoarselnutofRomanVitterallBrayymallsmallBeforetheybeputinitmustbestirredverywellforyespaceoftwoweeks。

“Areceitforink——1727

“WilliamSatherwaite。”

(Theabovereceiptisaliteralcopyoftheoriginal，nowinmypossession。Itpurportstohavebeenwrittenwiththemixtureitspecifies。)

*******

“M。deChampnorandM。F。Malepeyre，1862，intheirMannelstatethatRibaucourt’sinkisoneofthebesttheninuse。Theformulaforitspreparationisasfollows：

Aleppogalls，incoarsepowder，8ounces。

Logwoodchips，4“

Sulphateofiron，4“

Powderedgum-arabic，3“

Sulphateofcopper，1“

Crystallizedsugar，1“

Boilthegallsoflogwoodtogetherintwelvepoundsofwaterforanhour，ortillhalfthewaterhasbeenevaporated；strainthedecoctionthroughahairsieve，andaddtheotheringredients；stirtillthewhole，especiallythegum，bedissolved；andthenleaveatrestfortwenty-fourhours，whentheinkistobepouredoffintoglassbottlesandcarefullycorked。

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“Mr。J。Horsleygivesthefollowingreceipt：

Triturateinamortarthirty-sixgrainsofgallicacidwiththreeandone-halfouncesofstrongdecoctionoflogwood，putitintoaneightouncebottle，togetherwithoneounceofstrongammonia。

Nextdissolveoneounceofsulphateofironinhalfanounceofdistilledwaterbytheaidofheat；

mixthesolutionstogetherbyafewminutes’

agitation，whenagoodinkwillbeformed，perfectlyclear，whichwillkeepgoodanylengthoftimewithoutdepositing，thickening，orgrowingmouldy，whichlatterqualityisagreatdesideratum，asinkundergoingthatchangebecomesworthless。Itwillnotdotomixwithordinaryink，normustgreasypaperbeusedforwritingonwithit。”——

ChemicalNews(1862)。

*******

“NewIndelibleMarkingInk——Dr。Elsnergivesthefollowingasastampinginkforgoodsbeforeundergoingbleaching，ortreatingwithacidsoralkalis。ItconsistsmerelyofoneounceoffineChinesevermilionandonedrachmofprotosulphateofiron，welltrituratedwithboiledoilvarnish。”

********

“PutAleppogalls，wellbruised，41/2oz。andlogwoodchipped，1oz。with3pintssoftwater，intoastonewaremug：slowlyboil，untilonequartremains：

add，wellpowdered，thepuregreencrystalsofsulphateofiron，21/2oz。bluevitriolorverdigris，(Ithinkthelatterbetter)1/2oz。gumarabic2oz。andbrownsugar，2oz。Shakeitoccasionallyaweekaftermaking：thenafterstandingaday，decantandcork。Topreventmouldingaddalittlebrandyoralcohol。

“Thecommoncopperaswillnotanswersowellasithasalreadyabsorbedoxygen。”

*******

“Pouragallonofboilingsoftwateronapoundofpowderedgalls，previouslyputintoapropervessel。Stopthemonthofthevessel，andsetitinthesuninsummer，orinwinterwhereitmaybewarmedbyanyfire，andletitstandtwoorthreedays。Thenaddhalfapoundofgreenvitriolpowdered，andhavingstirredthemixturewelltogetherwithawoodenspatula，letitstandagainfortwoorthreedays，repeatingthestirring，whenaddfurthertoit5ouncesofgumarabicdissolvedinaquartofboilingwater，andlastly，2ouncesofalum，afterwhichlettheinkbestrainedthroughacoarselinenclothforuse。

“Another。Agoodanddurableinkmaybemadebythefollowingdirections：To2pintsofwateradd3ouncesofthedarkcolouredrough-

skinnedAleppogallsingrosspowder，andofraspedlogwood，greenvitriol，andgumarabic，each，1oz。

“Thismixtureistobeputintoaconvenientvessel，andwellshakenfourorfivetimeaday，fortenortwelvedays，attheendofwhichtimeitwillbefitforuse，thoughitwillimprovebyremaininglongerontheingredients。Vinegarinsteadofwatermakesadeepercolouredink；butitsactiononpenssoonspoilsthem。”

********

“Beatupwelltogetherinanironmortarthefollowingingredientsinadrystate；viz。8oz。ofbestbluegall-nuts，4oz。ofcopperas，orsulphateofiron，2oz。ofcleargumarabic，and3pintsofclearrainwater。

“Whenproperlypowdered，puttotheabove；

letthewholebeshakeninastonebottlethreeorfourtimesaday，forsevendays，andattheendofthattime，pourtheliquidoffgentlyintoanotherstonebottle，whichplaceinanairysituationtopreventitfrombecomingfoulormothery。

Whenusedputtheliquidintotheink-standasrequired。”

Take6quarts(beermeasure)ofclearwater，softorhard，andboilinitforaboutanhour4oz。

ofthebestCampeachylogwood，chippedverythinacrossthegrain，adding，fromtimetotime，boilingwatertosupplyinpartthelossbyevaporation；

straintheliquorwhilehot，andsufferittocool。Iftheliquoristhenshortof5quarts，makeitequaltothisquantitybytheadditionofcoldwater。Afterwhichlet1lb。ofbruisedbluegalls，or20oz。ofthebestcommongalls，beadded。Letapastebepreparedbytriturating4oz。ofsulphateofiron(greenvitriol)calcinedtowhiteness，andlethalfanounceofacetiteofcopper(verdigris)

bewellincorporatedtogetherwiththeabovedecoctionintoamass，throwinginalso3oz。ofcoarsebrownsugarand6oz。ofgumSenegal，orArabic。

Putthematerialsintoastonebottleofsuchasizeastohalffillit；letthemouthbeleftopen，andshakethebottlewell，twiceorthriceaday。Inaboutafortnightitmaybefilled，andkeptinwell-

stoppedbottlesforuse。Itrequirestobeprotectedfromthefrost，whichwouldconsiderablyinjureit。”

Infuseapoundofpomegranatepeels，brokentoagrosspowder，for24hoursinagallonandahalfofwater，andafterwardsboilthemixturetill1-3dofthefluidbewasted。Thenaddtoit1lb。

ofRomanvitriol，and4oz。ofgumarabicpowdered，andcontinuetheboilingtillthevitriolandgumbedissolved，afterwhichtheinkmustbestrainedthroughacoarselinencloth，whenitwillbefitforuse。

“Thisinkissomewhatmoreexpensive，andyetnotsogoodinhueasthatmadebythegeneralmethod，butthecolourwhichithasisnotliabletovanishorfadeinanylengthoftime。”

********

“Infuseapoundofgallspowderedand3ouncesofpomegranatepeels，inagallonofsoftwaterforaweek，inagentleheat，andthenstrainoffthefluidthroughacoarselinencloth。Thenaddtoit8oz。ofvitrioldissolvedinaquartofwater，andletthemremainforadayortwo，preparinginthemeantimeadecoctionoflogwood，byboilingapoundofthechipsinagallonofwater，till1-3dbewasted，andthenstrainingtheremainingfluidwhileitishot。Mixthedecoctionandthesolutionofgallsandvitrioltogether，andadd5oz。ofgumarabic，andthenevaporatethemixtureoveracommonfiretoabout2quarts，whentheremaindermustbeputintoavesselproperforthatpurpose，andreducedtodryness，byhangingthevesselinboilingwater。Themassleft，afterthefluidhaswhollyexhaled，mustbewellpowdered，andwhenwantedforuse，maybeconvertedintoinkbytheadditionofwater。”

********

“Tenpartsoflogwoodaretobeexhaustedwitheightyofboilingwater。Tothesolutiononethousandthofitsweightofyellowchromateofpotashistobeaddedgradually。Theliquidturnsbrownandatlastblue-black。Nogumisneeded，andtheinkisnotremovedbysoakinginwater——

ChemicalGazette，London(1850)。”

********

“Shellac，2oz。；borax，1oz。；distilledorrainwater，18oz。Boilthewholeinacloselycoveredtinvessel，stirringitoccasionallywithaglassroduntilthemixturehasbecomehomogeneous；filterwhencold，andmixthefluidsolutionwithanounceofmucilageorgumarabicpreparedbydissolving1oz。ofgumin2oz。ofwater，andaddpulverizedindigoandlampblackadlibitum。Boilthewholeagaininacoveredvessel，andstirthefluidwelltoeffectthecompletesolutionandadmixtureofthegumarabic。Stiritoccasionallywhileitiscooling；

andafterithasremainedundisturbedfortwoorthreehours，thattheexcessofindigoandlamp-

blackmaysubside，bottleitforuse。Theaboveinkfordocumentarypurposesisinvaluable，beingunderallordinarycircumstances，indestructible。

Itisalsoparticularlywelladaptedfortheuseofthelaboratory。Fivedropsofcreosoteaddedtoapintofordinaryinkwilleffectuallypreventitsbecomingmouldy。”

********

“InNovember，1854，Mr。GraceCalvertreadapaperbeforetheLondonSocietyofArtsinwhichhesaidthathehopedbeforelongsomevaluabledyeingsubstancesotherthancarbo-azoticacidwouldbepreparedfromcoaltar。

“Inanotherpaperreadbeforethesamesocietyin1858hesaid：’Thisexpectationhasnowbeenfulfilled。Messrs。PerkinsandChurchhaveobtainedseveralbluecoloringsubstancesfromthealkaloidsofcoaltar，andonefromnaphthalene。’

AlsothathimselfandMr。CharlesLowehadsucceededinobtainingcoaltarproductsyieldingcolorsofabeautifulpink，red，violet，purple，andchocolate。(Thesewerenotsolubleinwater)。”

********

“AmongvegetablesubstancesusefulintheartsisonethathaslongbeenknowninNewGrenadaunderthenameoftheink-plant，asfurnishingajuicewhichcanbeusedinwritingwithoutpreviouspreparation。Characterstracedwiththissubstancehaveareddishcoloratfirst，whichturnstoadeepblackinafewhours。Thisjuiceissaidtobereallylessliabletothickenthanordinaryink，andnottocorrodesteelpens。Itresiststheactionofwater，andispracticallyindelible。Theplantisknownascoryariathymifolia。”

********

“Desormeauxrecommendsthatthesulphateofironbecalcinedtowhiteness；coarsebrownsugarinsteadofsugarcandy；1/4oz。acetateofcopper，insteadofoneounceofthesulphate，andadroportwoofcreosoteoressentialoilofclovestopreventmoulding。”(SeeRibaucourtreceipt，p。194。)

********

“Mr。JohnSpillercommunicatedtotheLondonChemicalNews(1861)apaperontheemploymentofcarbonasameansofpermanentrecord。Theimperishablenatureofcarbon，initsvariousformsoflamp-black，ivory-black，wood-charcoal，andgraphiteorblacklead，holdsoutmuchgreaterpromiseofbeingusefullyemployedinthemanufactureofapermanentwritingmaterial；since，forthissubstance，initselementaryconditionandatordinarytemperatures，thereexistsnosolventnorchemicalreagentcapableofaffectingitsalteration。

“Thesuggestionrelativetothemodeofapplyingcarbontothesepurposes，whichitisintendedmoreparticularlynowtoenunciate，dependsonthefactoftheseparationofcarbonfromorganiccompoundsrichinthatelement，sugar，gum，etc。，bythecombinedoperationofheatandofchemicalreagents，suchassulphuricandphosphoricacids，whichexertadecomposingactioninthesamedirection；andbysuchmeanstoeffectthedepositionofthecarbonwithintheporesofthepaperbyaprocessofdevelopmenttobeperformedafterthefluidwritinginkhasbeentoacertainextentabsorbedintoitssubstance——asystemofformationbywhichaconsiderableamountofresistance，bothtochemicalandexternalinfluences，appearstobesecured。Aninkofthefollowingcompositionhasbeenmadethesubjectofexperiment：

“Concentratedsulphuricacid，deeplycoloredwithindigo……1fluidounce。

Water，……6““

LoafSugar，……1ounce，troy。

Strongmucilageofgum-arabic2to3fluidounces。

“Writingtracedwithaquillorgoldpendippedinthisinkdriestoapalebluecolor；butifnowaheatedironbepassedoveritssurface，orthepageofmanuscriptbeheldnearafire，thewritingwillquicklyassumeajetblackappearance，resultingfromthecarbonizationofthesugarbyawarmacid，andwillhavebecomesofirmlyengraftedintothesubstanceofthepaperastoopposeconsiderabledifficultytoitsremovalorerasurebyaknife。Onaccountofthedepthtowhichthewrittencharactersusuallypenetrate，thesheetsofpaperselectedforuseshouldbeofthethickestmake，andgoodwhitecartridgepaper，orthatknownas’creamlaid，’preferredtosuchasarecoloredbluewithultramarine；for，inthelattercase，ableachedhaloisfrequentlyperceptiblearoundtheoutlinesoftheletters，indicatingthepartialdestructionofthecoloringmatterbythelateralactionoftheacid。

“Thewritingproducedinthismannerseemsindelible；

itresiststheactionof“saltsoflemon。”

andofoxalic，tartaric，anddilutedhydrochloricacids，agentswhichrendernearlyillegiblethetracesofordinaryblackwritingink；neitherdoalkalinesolutionsexertanyappreciableactiononthecarbonink。Thismaterialpossesses，therefore，manyadvantageousqualitieswhichwouldrecommenditsadoptionincaseswherethequestionofpermanenceisofparamountimportance。Butitmust，ontheotherhand，beallowedthatsuchanink，initspresentform，wouldbutinefficientlyfulfilmanyoftherequirementsnecessarytobringitintocommonuse。Thepeculiarmethodofdevelopmentrenderingtheapplicationofheatimperative，andthatofatemperaturesomewhatabovetheboilingpointofwater，togetherwiththecircumstancethatitwillbefoundimpossiblewithathinsheetofpapertowriteonbothsides，mustcertainlybecountedamongitsmoreprominentdisadvantages。”

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“Fire-proofinkforwritingorprintingonincombustiblepaperismadeaccordingtothefollowingrecipe：Graphite，finelyground，22drams；

copalorotherresinousgum，12grains；sulphateofiron，2drams；tinctureofnutgalls，2drams；

andsulphateofindigo，8drams。Thesesubstancesarethoroughlymixedandboiledinwater，andtheinkthusobtainedissaidtobebothfire-

proofandinsolubleinwater。Whenanyothercolorbutblackisdesired，thegraphiteisreplacedbyanearthlymineralpigmentofthedesiredcolor。”

********

“IneradicableWriting——AFrenchtechnicalpaper，speciallydevotedtotheartandscienceofpapermanufacture，statesthatanyalterationsorfalsificationsofwritingsinordinaryinkmayberenderedimpossiblebypassingthepaperuponwhichitisintendedtowritethroughasolutionofonemilligram(0。01543Englishgrain)ofgallicacidinasmuchpuredistilledwateraswillfilltoamoderatedepthanordinarysoup-plate。Afterthepaperthuspreparedhasbecomethoroughlydry，itmaybeusedasordinarypaperforwriting，butanyattemptmadetoalter，falsify，orchangeanythingwrittenthereon，willbeleftperfectlyvisible，andmaythusbereadilydetected。”

********

“ExchequerInk——To40poundsofgalls，add10poundsofgum，9poundsofcopperas，and45

gallonsofsoftwater。Thisinkwillendureforcenturies。”

********

“Takeofoiloflavender，120grains，ofcopalinpowder，17grains，redsulphuretofmercury，60

grains。Theoiloflavenderbeingdissipatedwithagentleheat，acolourwillbeleftonthepapersurroundedwiththecopal；asubstanceinsolubleinwater，spirits，acids，oralkalinesolutions。

“Thiscompositionpossessesapermanentcolour，andaMSS。writtenwithit，maybeexposedtotheprocesscommonlyusedforrestoringthecolourofprintedbooks，withoutinjurytothewriting。Inthismannerinterpolationswithcommoninkmayberemoved。”

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Boilparchmentslipsorcuttingsofgloveleather，inwatertillitformsasize，which，whencool，becomesoftheconsistenceofjelly，then，havingblackenedanearthernplate，byholdingitovertheflameofacandle，mixupwithacamelhairpencil，thefinelamp-blackthusobtained，withsomeoftheabovesize，whiletheplateisstillwarm。Thisblackrequiresnogrinding，andproducesaninkofthesamecolour，whichworksasfregywiththepencil，andisasperfectlytransparentasthebestIndianink。”

********

“Insteadofwaterusebrandy，withthesameingredientswhichenterintothecompositionofanyink，anditwillneverfreeze。”

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“BacteriainInk——AccordingtoexperimentswhichhaverecentlybeencompletedatBerlinandLeipzigbytheleadingbacteriologistsofGermanytheordinaryinksliterallyteemwithbacillaofadangerouscharacter，thebacteriatakentherefromsufficingtokillmiceandrabbitsinoculatedtherewithinthespaceoffromonetothreedays。”

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“Themosteasyandneatmethodofforminglettersofgoldonpaper，andforornamentsofwritingis，bythegoldammoniac，asitwasformerlycalled：themethodofmanagingwhichisasfollows：

“Takegumammoniacum，andpowderit；andthendissolveitinwaterpreviouslyimpregnatedwithalittlegumarabic，andsomejuiceofgarlic。

Thegumammoniacumwillnotdissolveinwater，soastoformatransparentfluid，butproducesamilkyappearance；fromwhencethemixtureiscalledinmedicinethelacammoniacum。Withthelacammoniacumthusprepared，drawwithapencil，orwritewithapenonpaper，orvellum，theintendedfigureorlettersofthegilding。Sufferthepapertodry；andthen，oranytimeafterwards，breathonittillitbemoistened；andimmediatelylayleavesofgold，orpartsofleavescutinthemostadvantageousmannertosavethegold，overthepartsdrawnorwrittenuponwiththelacammoniacum；andpressthemgentlytothepaperwithaballofcottonorsoftleather。Whenthepaperbecomesdry，whichashorttimeorgentleheatwillsooneffect，brushoff，withasoftpencil，orruboffbyafinelinenrag，theredundantgoldwhichcoveredthepartsbetweenthelinesofthedrawingorwriting；andthefinesthairstrokesofthepencilorpen，aswellasthebroader，willappearperfectlygilt。”

Itisusualtoseeinoldmanuscripts，thatarehighlyornamented，lettersofgoldwhichriseconsiderablyfromthesurfaceofthepaperorparchmentcontainingtheminthemannerofembossedwork；andofthesesomearelessshining，andothershaveaveryhighpolish。Themethodofproducingtheselettersisoftwokinds；theonebyfrictiononaproperbodywithasolidpieceofgold：theotherbyleafgold。Themethodofmakingtheselettersbymeansofsolidgoldisasfollows：

“Takechrystal；andreduceittopowder。Temperitthenwithstronggumwater，tillitbeoftheconsistenceofpaste；andwiththisformtheletters；

and，whentheyaredry，rubthemwithapieceofgoldofgoodcolour，asinthemannerofpolishing；andtheletterswillappearasifgiltwithburnishtgold。”

(Kunckel，inhisfiftycuriousexperiments，hasgiventhisreceipt，butomittedtotaketheleastnoticeofthemannertheselettersaretobeformed，thoughthemostdifficultcircumstanceintheproductionofthem。)

CHAPTERXXII。

INKINDUSTRY。

IMPORTANCEOFHONESTINKMANUFACTURE——ABSENCE

OFINFORMATIONASTONAMESOFMOSTANCIENTINK

MAKERS，——WHERETOLOOKFORANCIENTINK——THEIR

PHENOMENALIDENTITY——INKANDPAPERASASIATIC

INVENTIONSENTEREUROPEINTHETWELFTHCENTURY——

BOTHINGENERALUSEINTHEFOURTEENTH

CENTURY——MONKSANDSCRIBESASTHEIROWNINK

MANUFACTURERS——MODERNINDUSTRYOFINKBEGINS

IN1625——ITSGROWTHANDPRESENTSITUATION——THE

GENERALIGNORANCEOFTHESUBJECT——INKINDUSTRY

INTHEEIGHTEENTHCENTURY——THEFIRSTPIONEERS

ABROADANDTHOSEATHOME——OBSERVATIONS

RESPECTINGINKPHENOMENAOFTHEPASTEIGHTY

YEARS——WHATSOMEINKMAKERSSAYABOUTIT——LITTLE

DEMANDFORPUREINKS——SOMESKETCHESOFTHE

LEADINGINKMANUFACTURERSOFTHEWORLD——ESTIMATION

OFQUANTITYOFINKMADEINTHEUNITED

STATES——THE“LIFE“OFAMARKMADEWITHORDINARY

WRITINGFLUID——ESTIMATIONOFMOSTINKSBYPROFESSORS

BAIRDANDMARKOE——FORMULAOFTHEOFFICIAL

INKOFTHESTATEOFMASSACHUSETTS——VIEWS

OFSOMEPROMINENTINKMANUFACTURERSABOUT

SUCHINK——SOMECOMMERCIALNAMESBESTOWEDON

DIFFERENTINKS——THE200ORMORENAMESOFINK

MANUFACTURERSOFTHENINETEENTHCENTURY。